(New York Times) — Early one morning last September, more than 50 members of the Police Department’s Internal Affairs Bureau gathered in Lower Manhattan during a continuing investigation into widespread ticket-fixing by New York officers. They were briefed and divided into teams, and then they piled into cars and vans bound for all 12 precinct station houses in the Bronx and others around the city to seize copies of tens of thousands of summonses. But almost as soon as the Internal Affairs teams set out — and long before the first one arrived at its target station house — their plans were exposed by a betrayal that some investigators suggest is far more insidious than the ticket-fixing itself, according to a person with knowledge of the events of that day a year ago. A union official was captured on a wiretap telling a union colleague who was under scrutiny in the case that he had received a call from someone in the Internal Affairs Bureau, and that the caller had warned him that the investigators were on the way, the source said. The call came shortly after the teams headed out toward the precincts.